Here's a useful tip about FF that I read somewhere on the web.
When you begin to type a form field on a web page or a URL on the address bar, you usually get many entries that matches the text you are typing (autocomplete feature), right?
Sometimes you simply want to delete a specific entry suggested by the browser, both inside a form field (e.g. a wrong e-mail address/username) or a web address (e.g. www.playboy.com).
How to do that?
Simple! Just highlight that "annoying entry" pressing cursor down key, then press both SHIFT + DELETE keys. That entry will be zapped!
Take also a look to this page to see all Firefox shortcuts, for Windows, Linux and Mac.
That tip works only in FF: do you know a way to do that in IE 6/7?